Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
With schema coverage at 57%, the description compensates well by naming the filters (year_from, year_to, field, open_access, source), enumerating the source values, and explaining that source=all mixes indexes. Only 'limit' and the semantics of year bounds are left solely to the schema.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.